Collection of Treatises on the Occult Sciences

This advantage, that they can form no utterance unless the vowels so permit; which must be drawn from the name of the proposition to effect the subtlety of this art. To facilitate the understanding thereof, it is absolutely necessary to take a, e, i, o, u, to each of which is assigned its own proper number as follows: as the a must have the number 10, to the e one adds 5, which makes 15; to the i another 5; and likewise for the others, increasing by 5 and 5 until the letter u. And herein lies the subtlety of this scientific art for knowing all that one desires; and for greater clarification, let us propose an example:
a, e, i, o, u 10 15 20 25 30 with their values when the vowels stand alone; and to proceed as if you wished to calculate a name having only a single vowel of this kind, then this vowel possesses its full force and has the